Well, if you download it from the web you'll be getting Internet Explorer 6.0 Service Pack 1 - the CD she has may not be SP1.. Getting it from the web ensures that you get the latest version - then it's just a matter of going and downloading the latest cumulative security patch, available from Microsoft's site as well.

To download the install program for IE6SP1: http://www.microsoft.com/windows/ie/...1/download.asp

To download the latest ***. security patch:
http://www.microsoft.com/windows/ie/...al/default.asp